1. A wastewater treatment plant serving a city of 200,000 discharges 1.10 m/s of treated effluent having an ultimate BOD of 50.0 mg/L into a stream that has a flow of 8.70 m³/s and a BOD of its own equal to 6.0 mg/L. The deoxygenation constant ka, is 0.20/day. a. Assuming complete and instantaneous mixing, estimate the ultimate BOD of the river just downstream from the outfall. b. If the stream has a constant cross section, so that it flows at a fixed speed equal to 0.30 m/s, estimate the BOD remaining in the stream at a distance 30,000 m downstream. 2. The wastewater in the question above has a dissolved oxygen concentration of 2.0 mg/L and a discharge rate of 1.10 m³/s. The river that is receiving this waste has BO equal to 8.3 mg/L, a flow rate of 8.70 m/s, and a temperature of 20°C. Assuming complete and instantaneous mixing, estimate the initial dissolved oxygen deficit of the mixture of wastewater and river water just downstream from the discharge point.

1. A wastewater treatment plant serving a city of 200,000 discharges 1.10 m/s of treated effluent having an ultimate BOD of 50.0 mg/L into a stream that has a flow of 8.70 m³/s and a BOD of its own equal to 6.0 mg/L. The deoxygenation constant ka, is 0.20/day. a. Assuming complete and instantaneous mixing, estimate the ultimate BOD of the river just downstream from the outfall. b. If the stream has a constant cross section, so that it flows at a fixed speed equal to 0.30 m/s, estimate the BOD remaining in the stream at a distance 30,000 m downstream. 2. The wastewater in the question above has a dissolved oxygen concentration of 2.0 mg/L and a discharge rate of 1.10 m³/s. The river that is receiving this waste has BO equal to 8.3 mg/L, a flow rate of 8.70 m/s, and a temperature of 20°C. Assuming complete and instantaneous mixing, estimate the initial dissolved oxygen deficit of the mixture of wastewater and river water just downstream from the discharge point.

Structural Analysis

6th Edition

ISBN:9781337630931

Author:KASSIMALI, Aslam.

Publisher:KASSIMALI, Aslam.

Chapter2: Loads On Structures

Section: Chapter Questions

Problem 1P

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